Morgan Brian and Alexandra Popp collided during Tuesday's game, sending both players crashing to the turf.

Receive the latest health updates in your inbox

Alexandra Popp #18 of Germany suffers a head injury as she is checked on by Simone Laudehr #6 in the first half against the United States in the FIFA Women's World Cup 2015 Semi-Final Match at Olympic Stadium on June 30, 2015 in Montreal, Canada.

Germany coach Silvia Neid said forward Alexandra Popp did not have a concussion after banging heads with U.S. midfielder Morgan Brian in the first half of the women's World Cup semifinal.

Both returned quickly to the game.

"Alex had a laceration; she did not have a concussion," Neid said after the game, which the United States won 2-0 to reach the final. "If it had been worse, we would have taken her out."

Popp had blood soaking her hair after the collision in the penalty area in front of the U.S. goal. After being tended to by the medical staff on the field, both players left the match for a minute or so before returning.

Best of the Women's World Cup

Like many contact sports only recently coming to terms with the long-term risks of concussions, soccer has struggled to handle head injuries.

In the men's World Cup final in Brazil last summer, Germany midfielder Christoph Kramer stayed in the game after colliding with Argentina defender Ezequiel Garay. Kramer later had to be helped off the field and said he couldn't remember much from the collision — signature symptoms of a concussion.

Concussion researchers say sports need to develop protocols that do not rely on players and team doctors — who might have a conflict of interest that puts the athlete's health second to the desire to win — to assess their condition. Some suggest neutral doctors, and others want soccer to waive its three-substitute rule for a concussed player.

Meet the USA Women's World Cup Team

Neid said that was unnecessary, at least in this case.

"(Popp) was just bleeding a bit but she felt well, and she told me so," the coach said. "Why would I take her out then, if the player says to our doctor that she's well and our doctor can verify that?"

Other things of note:

REMATCH: The United States is back in the final for the second consecutive time. A Japanese victory over England on Wednesday would mean a rematch of the championship game four years ago.

No Asian team had won the World Cup until Japan beat the U.S. 3-1 in penalty kicks after a 2-2 draw in the 2011 final.

"I haven't thought about that until about 30 minutes ago, honestly," said American forward Alex Morgan, who entered the game at halftime as a substitute. "It was all about Germany up until the end of this game. The fact that it could possibly be Japan, I think is a great story line."

SLEEPING IN: England coach Mark Sampson is providing soccer fans back home an excuse to be late for work on Thursday — as long as they stay up to watch the sixth-rank Lionesses play defending champion Japan in the Women's World Cup semifinal.

Because of the time difference, the game will start at midnight in England. Sampson and the nation's federation provided an already signed late-to-work form.

It reads: "To whom it may concern. Please allow (fill in the name) to have a lie-in on the morning of Thursday 2 July."

It continues: "The (hashtag)Lionesses need the backing of the nation to help keep our dream alive."

On Tuesday, Sampson said he's offered his players the same deal: an opportunity to sleep in on Thursday.

England is making its deepest run in the tournament after failing to win an elimination game in three previous appearances. They've already attracted the support of Prince William, David Beckham and actress Emma Watson.

Midfielder Jill Scott and her teammates are wowed by the support they've received, especially notes from parents saying their daughters are becoming interested in getting into soccer.

"We're not stepping on that pitch just for us," Scott said. "We're stepping on the pitch for the whole of women's football, and hopefully we can carry on doing our country proud."